#include<netinet/in.h>   // sockaddr_in
#include<sys/types.h>    // socket
#include<sys/socket.h>   // socket
#include<stdio.h>        // printf
#include<stdlib.h>       // exit
#include<string.h>       // bzero

#define SERVER_PORT 155314
#define BUFFER_SIZE 1024
#define FILE_NAME_MAX_SIZE 512

int main()
{
    // 声明并初始化一个客户端的socket地址结构
    struct sockaddr_in client_addr;
    bzero(&client_addr, sizeof(client_addr));
    client_addr.sin_family = AF_INET;
    client_addr.sin_addr.s_addr = htons(INADDR_ANY);
    client_addr.sin_port = htons(0);

    // 创建socket，若成功，返回socket描述符
    int client_socket_fd = socket(AF_INET, SOCK_STREAM, 0);
    if(client_socket_fd < 0)
    {
        perror("Create Socket Failed:");
        exit(1);
    }

    // 绑定客户端的socket和客户端的socket地址结构 非必需
    if(-1 == (bind(client_socket_fd, (struct sockaddr*)&client_addr, sizeof(client_addr))))
    {
        perror("Client Bind Failed:");
        exit(1);
    }

    // 声明一个服务器端的socket地址结构，并用服务器那边的IP地址及端口对其进行初始化，用于后面的连接
    struct sockaddr_in server_addr;
    bzero(&server_addr, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    if(inet_pton(AF_INET, "127.0.0.1", &server_addr.sin_addr) == 0)
    {
        perror("Server IP Address Error:");
        exit(1);
    }
    server_addr.sin_port = htons(SERVER_PORT);
    socklen_t server_addr_length = sizeof(server_addr);

    // 向服务器发起连接，连接成功后client_socket_fd代表了客户端和服务器的一个socket连接
    if(connect(client_socket_fd, (struct sockaddr*)&server_addr, server_addr_length) < 0)
    {
        perror("Can Not Connect To Server IP:");
        exit(0);
    }

    // 输入文件名，并放到缓冲区buffer中等待发送
    char file_name[FILE_NAME_MAX_SIZE+1];
    bzero(file_name, FILE_NAME_MAX_SIZE+1);

    printf("Please Input File Name On Client:\t");
    scanf("%s", file_name);

    char buffer[BUFFER_SIZE];
    bzero(buffer, BUFFER_SIZE);
    strncpy(buffer, file_name, strlen(file_name)>BUFFER_SIZE?BUFFER_SIZE:strlen(file_name));

    // 向服务器发送buffer中的数据
    if(send(client_socket_fd, buffer, BUFFER_SIZE, 0) < 0)
    {
        perror("Send File Name Failed:");
        exit(1);
    }


    // 打开文件并读取文件数据
        FILE *fp = fopen(file_name, "r");
        if(NULL == fp)
        {
            printf("File:%s Not Found\n", file_name);
        }
        else
        {
            bzero(buffer, BUFFER_SIZE);
            int length = 0;
            // 每读取一段数据，便将其发送给服务器，循环直到文件读完为止
            while((length = fread(buffer, sizeof(char), BUFFER_SIZE, fp)) > 0)
            {
                if(send(client_socket_fd, buffer, length, 0) < 0)
                {
                    printf("Send File:%s Failed./n", file_name);
                    break;
                }
                bzero(buffer, BUFFER_SIZE);
            }

            // 关闭文件

            fclose(fp);
            printf("File:%s Transfer Successful!\n", file_name);
        char s[50];
        scanf("%s",s);
        send(client_socket_fd,"OK",BUFFER_SIZE,0);
        recv(client_socket_fd,buffer,BUFFER_SIZE,0);
        printf("%d words.\n",atoi(buffer));
    }

    close(client_socket_fd);
    return 0;
} 
